I know this feeling. I'm a 24-26 & currently have one babydoll set from YoursClothing. I did have another one from SimplyBe, but I accidentally put it in the wrong laundry load & the delicate baby pink material ended up a dirty purple-grey.
I tried to get it back to the original colour by soaking it in a special dye run removal chemical, but it didn't work. So I tried to dye it all black & it went a horrible rusty red-brown colour!
I'm gonna have another go at dying it when I can find a nylon black dye, coz it's my favourite set.
YoursClothing have a pretty good plus size range online (for some stupid reason, they stopped stocking plus size lingerie in their stores) & the staff at my local store said if you order & don't like it when it arrives, you can return it to your local store for a refund or to arrange a different size.
SimplyBe also have a pretty good range, though some of the bits they have are a bit naff quality-wise & some sizes aren't true-to-size.